additive processes
Additive processes are unique to other processing for THESE reasons.
What is
- directly fabricating the part/shape without need of mold
- "printing" the product layer by layer
THIS glass fabrication process falls under the category of casting, where glass is partially punched in then air is blown in to fill the rest of the mold
What is PRESS AND BLOW CASTING?
THIS is the only difference between the stress-strain curves from tensile and compression tests.
What is A NEGATIVE STRAIN VALUE?
Flexural tests can be easier to perform than tensile tests for THESE reasons for brittle materials like ceramics (list 3)
What is
- hard to make specimen in specific shape
- hard to grip without fracture
- low displacement
The cheapest method of additive processing is THIS, which dispenses melted polymer through a nozzle.
What is INK-JET DEPOSITION?
Piezoelectrics are made by THIS process, which creates thin ceramic sheets from a liquid suspension.
What is TAPE CASTING?
The elastic modulus has THIS relationship to the stress-strain curve.
What is THE SLOPE of the elastic region.
Stress = E * strain
THIS hardness test only differs from the Rockwell hardness test by the shape of its point load, using a spherical point instead of a pointed one.
What is the BRINELL HARDNESS TEST?
Fractures can occur in THESE two ways, where the material either breaks cleanly or deforms before fracturing.
THIS method of additive processing involves a container of liquid polymer, which is solidified in specific areas by a laser to create more precise shapes.
What is STEREOLITHOGRAPHY?
Polymers are often fabricated through THESE two methods.
What are SPINNING FIBERS and POLYMER FILMS?
For a uniaxial material, Poisson's ratio changes in THIS way between tensile and compression tests.
What is NO CHANGE?
The Vickers micro-hardness test is unique for THIS reason.
What is:
it has a smaller indenter, so it can measure hardness of individual phases in a material
Impact fracture can be tested with THIS test, where the material is hit with high stress over a short period of time. By varying the temperature of the material, the ductile to brittle transition of this material can be observed.
What is the CHARPY TEST?
THIS method of additive processing requires the round powder produced from being sprayed with atomizing vapor, which is then selectively melted together with a laser.
What is SELECTIVE LASER SINTERING?
Heat treatment/annealing can improve the material in THESE possible ways. (list 3)
What are:
- grain refinement (aligning grains to be more ductile)
- relieving internal stress
- phase transformation
Materials with THIS property generally have a lesser toughness.
What is a BRITTLE material?
What is TWINNING?
Creep is different from fracturing for THESE two reasons.
What is:
- at elevated temperatures (40% of melting)
- stress must be CONSTANT, no slow increases
Selective laser sintering is expensive and wasteful for THESE reasons.
What is
- heat affected powder cannot be used again.
explain age hardening of aluminum alloys
good job
An increase in temperature results in THESE changes to the Elastic modulus, yield strength, Poisson's ratio, and tensile strength.
E: decreases
yield strength: decreases
Poisson's ratio: unchanged
TS: depends
From flexural testing a large sample, a graph of the frequency of tensile strengths can be produced. Ductile vs brittle materials produce THESE two different types of distributions.
What are GAUSSIAN and WEINBULL distributions.
THIS type of failure occurs due to dynamic, periodic stress, typically at stresses lower than that from a static load. This usually occurs without warning and no deformation.
What is FATIGUE?